From this chapter of the guide, you can find out what are the Cargo Crates in Deep Rock Galactic, how to find them and how to open them.
While exploring caves in Deep Rock Galactic, players also have about a 15% chance of finding Cargo Crates. The cargo crate is a large black-and-yellow container that cannot be missed. To open this container you will need two large batteries.
The batteries are scattered somewhere around the crate, so you'll have to look for them. The batteries are yellow and black and emit a distinctive "beep" sound so if you can't see them just follow the sound. The batteries should be dug out with a pickaxe and manually carried to the crate. During transport, the character cannot perform any other activities as this will make him drop the battery.
Once you put two batteries in the cargo crate it still needs to be repaired and you need to use a hammer here. In order to fix the cargo crate, simply approach it and hold the action button (by default E key) longer.
After a short while, raw materials and materials of the planetary region, in which the crate was found, will begin to jump out from the crate. In addition, the player will also receive an additional prize in the form of a cosmetic item or a weapon skin.
The extra reward is not matched to a particular character class so if you play the Driller, for example, it is not said that you will receive a cosmetic item for that character. The rewards received from the cargo crates are completely random but won't be duplicated.